Introduction
Combinations of Korean medicine (KM) and Western medicine (WM) have been used in Korea since the introduction of WM. While both KM and WM have contributed to improving health, it has been reported that the dualized medical system does not work efficiently [
1]. Therefore, Korean-Western integrative medicine (KWIM), was introduced so that patients could benefit from both approaches. Currently, integrative medicine is a trend in which Chinese medicine models are internationally recognized [
2].
Facial paralysis is a neurological condition in which facial muscles are paralyzed on 1 side of the face due to facial nerve damage. It has been reported that 85% of facial paralysis cases are idiopathic. Facial paralysis may because by viral infections (e.g. Bell’s palsy, herpes simplex, herpes zoster oricus), bacterial infections (e.g. Lyme disease, leprosy), autoimmunity (e.g. Bell’s palsy, hypothyroidism), trauma, tumors, strokes, sarcoidosis of unknown etiology, diabetes, strokes (e.g. Bell’s palsy), and congenital conditions. Among these, Bell’s palsy, which is characterized by idiopathic peripheral neuropathy, accounts for the largest portion of facial nerve paralysis [
3–
5].
According to the “Clinical Practice Guidelines in KM for facial nerve paralysis” revised in 2016, Korean treatment methods include acupuncture, moxibustion, herbal medicine, aqua-acupuncture, electro-acupuncture, auricular acupuncture, scalp acupuncture, and Ohaeng-acupuncture, while Western treatment methods include drug therapy (steroids, antiviral drugs), physical therapy, eye treatment, and surgical treatment [
6].
Recently, a number of clinical studies [
3,
5,
8–
11] have compared the effectiveness of KM with KWIM in treating facial paralysis without a conclusion. Here, the effectiveness of KM and KWIM to treat Bell’s palsy were compared by performing a literature search of randomized controlled trials (RCTs).
Discussion
Facial paralysis is loss of movement of the facial muscles which are paralyzed on 1 side of the face. There are various causes of facial paralysis. Among them, Bell’s palsy, a idiopathic facial paralysis, accounts for the largest percentage [
3–
5]. WM uses steroids to treat facial palsy, which help to control inflammation and reduce edema around facial nerves. Furthermore, antiviral, peripheral vasodilators, and other physical therapy options have been used [
12,
13]. In KM, acupuncture, herbal medicine, aqua-acupuncture, electro-acupuncture, moxibustion are practiced.
In Korea, KM and WM coexist as KWIM, which uses practices from both KM and WM to treat patients, and in the case of Bell’s palsy this may be beneficial. In addition to studies that compared the effectiveness of KM with KWIM, there are RCT studies that examine the effectiveness of KWIM. Gökçe Kütük et al [
14] reported better resolve of nerve dysfunction, a decrease in paralysis severity, and better functional recovery with electro-acupuncture in conjunction with WM therapy. Liu [
15] compared KWIM using drugs and acupuncture with KWIM using drugs, acupuncture, and herbal medicine, and reported that the latter was a more effective KWIM.
In this study, among Bell’s palsy integrative medicine, the effects of KM and KWIM were compared. Treatment methods reported in the “Clinical Practice Guideline in KM for facial nerve paralysis,” revised in 2016, were used as the criteria for distinguishing between KM and WM treatments [
6].
There are many ways to show the degree of facial paralysis including the degree of facial paralysis which was assessed using House Brackmann grading system (HBGS), Yanagihara’s unweighted grading system, detailed evaluation of facial symmetry and clinical efficacy. Among them, HBGS is the most representative in this review, where 4 of the 6 studies evaluated the degree of facial paralysis using HBGS. HBGS evaluates the degree of facial paralysis in 6 stages. Yanagihara’s unweighted grading system consists of a total of 40 points by visually assessing each motion presented and scoring it. Detailed evaluation of facial symmetry may also be used to describe the degree of recovery for each part of the face in detail. Qiao and Yan [
10] evaluated by clinical efficacy, classified HBGS Phase 1 as recovery, HBGS Phase 2 as apparent results, HBGS Phase 3 as effective results, and HBGS Phase 4–6 as no effects. Similarly, Li [
11] also evaluated the effectiveness of the treatment based on clinical efficacy (
Tables 7–
10) [
16–
18].
In all of the 6 included studies, the patient’s symptoms improved after treatment. Both KM and KWIM were effective in treating Bell’s palsy. However, a comparison of the effectiveness of KW and KWIM did not produce consistent results. Thus, considering statistically significant studies, Park et al [
8] reported that KWIM was more effective 1 week after treatment than KM, and Qiao and Yan [
10] and Li [
11] studies reported that KWIM was more efficacious than KM by comparing symptoms before and after treatment. Therefore, KM and KWIM are both effective in Bell’s palsy, and KWIM is more effective than treatment with KM alone.
One of the most representative features of KM is that the treatment depends on the patient’s overall condition, not the symptoms. This study also shows that both KM and KWIM were effective, but differences can be observed only when looking at the statistically significant results. In studies in which prescriptions varied according to the patient’s condition through dialectics, KM and KWIM were both effective during the treatment period. On the other hand, studies that gave everyone the same herbal medicine had a period of treatment that was effective, but not significant. Through this, the importance of different prescriptions through dialectics in KM is highlighted.
Among the treatments used for KWIM, acupuncture, and herbal medicine were the most commonly used KM, while drug therapy was the most typically used in WM [
19]. In this review, all 6 studies used acupuncture, and 5 of them used herbal medicine. In KWIM, drug therapy and KM (acupuncture/herbal medicine) was used.
In a previous literature review of acupuncture for Bell’s palsy, the meridians most used were the stomach, bladder, large intestine, and triple energizer, and the most used acupoints were ST4, ST6, LI4, GV26, ST2, TE17, and ST3 [
20]. This study also observed a similar use of meridians. In this study, the stomach meridian with 8 acupoints, gallbladder meridian with 5 acupoints, liver meridian with 3 acupoints, bladder meridian, large intestine meridian, triple energizer meridian and small intestine meridian with 2 acupoints, lung meridian, kidney meridian, conception vessel and governor vessel with 1 acupoint were used. The acupoints most used were ST4, ST6, GB14, LI20 (5 studies), TE23, LI4, BL2 (4 studies), ST2, ST7,CV24, GV26, an acupoint located at the top of the ear and at the side of the eye (3 studies), GB20, SI18, BL1, TE17 (2 studies), ST36, ST41, ST43, KI10, GB1, GB21, GB41, LR4, SI5, LU8, LR3, LR8, and an acupoint located at center of eyebrows (1 study).
Steroids are known to be effective in treating Bell’s palsy. In particular, using steroids within a week of symptoms of Bell’s palsy reduces neurological edema and nerve damage [
13,
21]. Most of the included studies for this review also used steroids in KWIM. Looking at the statistically significant results, both KM and KWIM were effective in the treatment of Bell’s palsy, especially KWIM which was more effective than KM. In particular, studies have shown that KWIM is significantly more effective than KM alone in the early stages of treating Bell’s palsy [
13,
21]. Studies have also shown that while KWIM is still effective over a longer period, it becomes statistically less significant over time [
8,
22].
Steroid therapy may be restricted for use in vulnerable groups, such as those with diabetes, osteoporosis, digestive ulcers, high blood pressure, cardiovascular disease, and psychiatric problems. Steroid therapy is also associated with a number of complications that can affect the musculoskeletal system, as well as ophthalmological, gastrointestinal, cardiovascular, and metabolic abnormalities. Furthermore, withdrawal symptoms such as joint pain, muscle pain, fatigue, headache, emotional changes, and gastrointestinal problems can occur after treatment [
23]. Cho et al [
9] reported an increase in blood sugar as a side effect of KWIM. However, steroids are known only to have minor side effects when used as short-term therapy for 2 to 3weeks.
The Jadad scale is 1 of the evaluation tools that can be used to assess RCT studies by evaluating 3 items: “randomization,” “blinding,” and “an account of all factors.” The total score can range from 0–5 points. The report sets out how to categorize high quality (≥ 3 points) and low-quality (≤ 2) studies [
7]. It is reported that double-blinded studies often show negative results compared with non-blinded studies, but a double-blind study reduces the risk of bias [
24]. The studies included in this review were all rated below 2 points on the Jadad scale.
In summary, KM and KWIM are both effective in Bell’s palsy, and KWIM is more effective than treatment with KM alone. In particular, steroid-based KWIM is believed to be effective in the early stages of Bell’s palsy treatment. Steroids have few side effects when used as short-term therapy for 2–3 weeks, but there are concerns regarding side effects with long-term use. Therefore, steroids should be used in the early stages of Bell’s palsy treatment and subsequently reduced over time, with KM used to treat symptoms in the long-term. In addition, when using herbal medicine in both KM and KWIM, it is more effective to prescribe it according to dialectics.
There are several limitations to this study. The number of studies included is small, and the quality of the studies was low, making it difficult to make any definitive conclusions regarding the treatment of Bell’s palsy. Nevertheless, this current study may help in selecting a treatment method for Bell’s palsy, as it was observed that early treatment has a great effect on prognosis. In the future, high-quality studies that compare the effectiveness of KM and KWIM are required.